The image on the left in the figure below consists of alternating stripes of black/white, each stripe being two pixels wide. The image on the right is the Fourier spectrum of the image on the left, showing the dc term and the frequency terms corresponding to the stripes. (Remember, the spectrum is symmetric so all components, other than the dc term, appear in two symmetric locations.)

*Suppose that the stripes of an image of the same size are four pixels wide. Sketch what the spectrum of the image would look like, including only the dc term and the two highest-value frequency terms, which correspond to the two spikes in the spectrum above.

Why are the components of the spectrum limited to the horizontal axis?

What would the spectrum look like for an image of the same size but having stripes that are one pixel wide? Explain the reason for your answer.

Are the dc terms in (a) and (c) the same, or are they different? Explain.